When it comes to preventing increasingly sophisticated and malicious attacks to your corporate network and its data, simply slapping on a few security appliances and scanning for spam isn't enough. Hackers act fast and are changing tactics. Even more can be gained by taking the time to analyze the data that your tools can give you about the attacks your enterprise is thwarting - or the malware that makes its way through. Analysis can give CIOs and IT managers value information about what's working and what's not when it comes to security. In the Cisco 4Q11 Global Threat Report, the company has rounded up information gathered by its security products to create a picture of the state of cyber-security between Oct. 1 and Dec. 31, 2011. The report finds that while spam volume continues to decline, malware attacks are becoming more frequent; in fact, "33% of Web malware encountered was zero-day malware not detectable by traditional signature-based methodologies at the time of encounter," Cisco said. "Most importantly, regular review and understanding of the data can help uncover the elusive "black swan"-the types of surreptitious and malicious events that otherwise could fly below the radar." Here are the report's key findings.